And rapidly, with a series of ritual gestures, he uncoiled two wires connected to the portable battery buckled round his waist; plugged them simultaneously into the sides of his aluminum hat; touched a spring on the crownand antennæ shot up into the air; touched another spring on the peak of the brimand, like a jack-in-the-box, out jumped a microphone and hung there, quivering, six inches in front of his nose; pulled down a pair of receivers over his ears; pressed a switch on the left side of the hat-and from within came a faint waspy buzzing; turned a knob on the rightand the buzzing was interrupted by a stethoscopic wheeze and cackle, by hiccoughs and sudden squeaks.